Get rid of the cattails and you will make the pond less attractive to them - that's a good food source for them. Look into getting a few colony muskrat traps - they can catch more than one at a time unlike the conibears. They are placed the same way - in the run under water.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).